Scraping sound coming from Theta Transport


Why do some cd's make a strange sound like somethings scraping inside my Theta DaViD? I actually own two of these units and certain cd's make srange loud scraping sounds during playback. I've check the discs in other players and they play fine, but neither of my Theta DaViDs will play them. Enya, Norah Jones, Sting (DTS disc) Forget it!

If anyone has a clue please chime in. Theta was no help on the phone. They just play dumb, like no one has ever reported this problem before. Maybe I have the only two units that were ever affected?
128x128glen
Here's a quick update. My DaViD is playing less and less of what I put in it (cd's). I fear the end is near and that a trip to the factory for servicing is inevitable.

I while back this piece was giving me a lot of problems playing DVD's so I swapped it out with another DaViD from my bedroom system.

Luckly I live in CA and the turn around time to the factory and back seems to be less than three weeks. I'd say right now that one in every ten discs makes that peculiar scraping sound including a brand new disc I just bought (George Winston/ Night divides the day).

On the average this transport is spending around one week a year being serviced. Other than that I have no complaints, I've compared it to other transports and prefer it to everything in and around that price range, it's still the cornerstone of my digital front end in two systems. My upgrade path being the DaViD II with progressive scan when they start selling a little cheeper in the used market.
Gunbei, I don't know if it's a DVD vs. CD issue, I can't really explain it at all. My symptoms also seem different from those described by Glen. Also, my new unit hasn't given me any trouble. However, I'm using a glasses rag to wipe clean a disc ANY TIME I put it in, and I'm covering the unit with a cloth after I'm done (after it cools). I don't know if either is necessary, but I'm paranoid now because of the old unit's skipping and the trouble I had getting it replaced. I must say, I'm extremely pleased with Theta's sound (I use the Carmen with a IIIa DAC), after a somewhat thorough search. I'm just not happy with their customer service, since it was pretty clear there was something wrong with my transport, and they had it 3 times before replacing it. They continually denied that the problem could be happening, and now I see from Glen's post that this is their MO. Pretty shoddy for a $3 device that probably cost them $1k to build. -Dave
This is the first I have heard of this problem. When looking for a transport I read many threads regarding the Theta Datas, Pearl and Jade and never found anything relating to this.

I've owned a Pearl now for a year and half and it's been flawless. Is it possible this is more of a DVD mechnism issue? The Pioneer Stable Platter in my unit has been great.
my DaViD II seems to have problems reading HDCD's at the beginning of track 1...doesn't happen with redbooks...makes that kind of noise as it tries to track...doesn't happen with DVD's...I'm wondering if it's the laser...I'm trying to "track" down the problem myself
Thanks for the info. I am in the market for a transport. I am not getting a Theta.
Ha! My Carmen skipped like crazy on a bunch of disks, and just plain coughed up a few (of course, no other player responded this way). The factory had it 3 times before they would replace it under warranty - took nearly a year. They played dumb with me too, said it was my disks, etc. etc...

Great sound, but bad, bad service. BTW, enya discs seem to be particularly prone. I'd LOVE to hear the real explanation for this phenomenon.